Process of producing a cooling tower

ABSTRACT

A cooling tower, a process for producing a cooling tower, and a reinforcing element suitable for use in the process and tower are disclosed. The cooling tower, formed from a shell of reinforced concrete, is produced with a plurality of plate-like reinforcing elements adjacent to a surface of the shell. The reinforcing elements are disposed in at least one horizontal plane within the shell adjacent to and suspended from the shell surface. The reinforcing elements in a plane abut and are joined one to another, and are also joined to the shell at spaced points thereon. Each plate-like element includes a central channel communicating with trough-like ends for receiving a suitable reinforcing material which extends into recesses in the shell of the cooling tower adjacent the trough-like ends.

BACKGROUND AND BRIEF DESCRIPTION OF THE INVENTION

This invention relates to the production of cooling towers. It hasparticular application to the production of cooling towers formed fromannular reinforced shells of a desired curvature and made of reinforcedconcrete, sections of which are accessible by means of a ladder or aclimable or movable shell. The invention is directly related to aprocess for the production of a cooling tower, as well as the coolingtower itself, and a reinforcing element for use in the process and thetower.

Cooling towers are used for recooling the cooling water ofhigh-performance steam power plants. In "natural circulation" coolingtowers, cooling air, because of a "chimney effect", flows upwardlythrough the tower. At a specified height, the cooling air is returnedinto the tower and cooled, by use of a wet coolant such as cooling waterwhich is sprayed into the air or by use of a dry coolant used in aclosed-circuit network.

Known cooling towers typically take the form of a body of rotation.Natural draft cooling towers may take the form of a single-shellrotation hyperboloid, whose waist is in the upper third section of thetower.

Cooling towers made of reinforced concrete usually carry their load bythe aid of a supporting framework and a suitable foundation adapted toground conditions. The shell of the tower is usually erected on thesite, capable of withstanding all loads and stresses that occur. Becausethe main stresses that occur are from the weight of the tower and fromwind forces, the tower's ability to withstand buckling and vibration isof major importance.

Because of the steadily increasing performance of modern steam powerplants, the need for cooling the air coolant is increasing. Whereaspresent day cooling towers generally have a maximum height of 170 metersand a maximum diameter of about 120 meters, future heights of 200 metersand base diameters of upwards of 150 meters are envisioned.

With existing cooling towers, the wall thickness of the shells in thewaist portion is in the order of 16 to 18 centimeters. In the case ofstill larger cooling towers, in order to obtain adequate stability ofthe shell, it has been suggested that the shell be stiffened byhorizontal stiffening rings. Because of constructional difficulties andhigh costs, an installation with horizontal stiffening rings has notbeen found to be practical in the past.

Accordingly, one of the main purposes of the invention is to create aprocess for producing a cooling tower and a cooling tower itself and apreformed reinforcing element useful in such production and tower. Thetowers to which the invention is directed are typically annularlyreinforced shells of a desired meridian form, and the invention involvesa relatively simple and inexpensive installation of reinforcing rings inthe shells of such towers.

These objects are achieved in the present invention by the use of aplurality of plate-like reinforcing elements suspended from the shell inat least one horizontal plane by suspension elements connected tosuspension locations on the shell above the plane, and preferably withina plurality of horizontal planes, with the reinforcing elements in eachplane abutting and joined one to another and joined to the shell of thetower at spaced points thereon.

In accordance with a preferred embodiment of the invention, the shell ofthe cooling tower includes spaced-apart recesses in the form of slitspassing partly or completely through the shell. The plate-likereinforcing elements are connected together and to the shell by theapplication of a suitable reinforcing material, such as concrete, whichis bonded to the reinforcing elements, joining them one to another, andalso filling the recesses so as to join the reinforcing elements to theshell.

The plate-like reinforcing elements useful in this invention areadvantageously preformed with a middle solid region having a centralchannel therein which communicates with trough-like ends for receiving asuitable reinforcing material, such as concrete. That reinforcingmaterial bonds to the reinforcing element and is used to join oneelement to another and the elements to the shell of the tower. Thetrough-like ends of the reinforcing elements thus constitute filigreeplates integral with the middle solid region of the reinforcing element.The outer edge of that reinforcing element is advantageously bentupwardly; the inner edge of the reinforcing element adjacent to thetower shell includes a projection provided with a sealing element toproduce a seal between the adjacent recess in the tower shell and thereinforcing element, to prevent the leakage of reinforcing material whenthat material is applied to the central channel and trough-like ends ofthe reinforcing element to join adjacent reinforcing elements togetherand to bond the reinforcing elements to the tower shell.

The preformed reinforcing elements are advantageously all of the sameform. The channel referred to in the middle solid region of each elementis upwardly open, and may include reinforcing rods therein for thestrengthening of the element when the reinforcing material is pouredtherein. Anchorages are also included in the reinforcing elements usedfor suspending these elements from the tower. The reinforcing elementsmay also include other components mounted thereon useful in the coolingoperation of the tower.

The reinforcing elements are preferably mounted in place by the use of acrane. The reinforcing elements may also be suspended by hand from thelowest foothold within the tower itself.

A particular advantage of the invention is in the use of reinforcingelements which define stiffening rings in a cooling tower. Thereinforcing elements abut one another, are made of the same generalshape, and are only intermittently connected together and to the towershell by suitable material, such as concrete. Because the reinforcingelements are suspended from the shell of the cooling tower, it ispossible to complete the fabrication and installation of the stiffeningrings in the tower independently of the building of the tower structureitself, thereby causing no delay in the tower construction.

The invention will be more completely understood by reference to thefollowing detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the installation of a reinforcing element on a coolingtower shell.

FIG. 2 shows, in a later stage of the process, a reinforcing elementmounted on the tower shell.

FIG. 3 is a view looking downwardly on a reinforcing element mounted ona tower shell.

FIGS. 4, 5, and 6 are sectional views taken respectively along thesections I--I, II--II, and III--III in FIG. 3.

DETAILED DESCRIPTION

FIGS. 1 and 2 show, at different stages of the process, the suspendingof a preformed reinforcing element 1 inside a shell 4 of a coolingtower. The cooling tower is preferably formed of reinforced concrete, asis the reinforcing element. A "goose-beak" extension 6 of a crane isutilized, having a horizontal support surface 6a which supports thereinforcing element 1 during the installation of that element in thecooling tower. The reinforcing element 1 is mounted adjacent to theinside surface of the tower shell 4, extending inwardly from the shell.The reinforcing element includes a shell 2, preferably of concrete,which is open at its top portion and includes a border 12. A pluralityof reinforcing elements 1 are utilized, advantageously arranged in anannular ring in a horizontal plane around the inside of the shell. Thereinforcing elements 1 may be placed in a plurality of horizontal planesthroughout the cooling tower.

Each reinforcing element 1 is suspended from the tower shell 4 by meansof suspension elements 7, suspended from suspension locations 3 on thetower shell above the reinforcing element 1. The reinforcing elements 1are also joined to the tower in the vicinity of spaced-apart recesses 9,as will be described in more detail below. Sealing elements 16 areincluded to prevent the escape of reinforcing material such as concrete,as will also be explained in more detail below.

The reinforcing elements 1 are thus suspended at the height of therecesses 9 throughout the shell in horizontal annular planes of theshell and constitute stiffening or reinforcing rings on the shell. Thesuspension elements 7 may be fitted in place at the suspension locations3 on the tower shell 4 from the lowermost step 22 of ladder 20. Thatladder is moved higher as the process proceeds, since the reinforcingelements are typically added to the tower from the bottom portion to thetop portion thereof. After each reinforcing element 1 is suspended onthe tower shell by use of the suspension elements 7 (which attach to thereinforcing elements 1 by anchorages 19 included therein), each pair ofadjacent reinforcing elements have a reinforcing material appliedthereto, such as concrete, which bonds to the adjacent reinforcingelements, joining them together, and also extends inwardly into therecesses 9, bonding the reinforcing elements to the tower shell 4. Thereinforcing material may be applied by use of a ladder 24 (FIG. 2)without requiring use of the ladder or framework assembly 20.

FIGS. 3 to 6 provide a better understanding of the application of thereinforcing material just mentioned that connects together adjacentreinforcing elements 1 and also connects those elements to the towershell 4. The reinforcing element 1 is typically rectangular in shape(when viewed from above in the tower as in FIG. 3). The reinforcingelement 1 is constituted of a middle solid region 10 and trough-likeends 2 which may constitute upwardly open concrete shells. Thelengthwise edge of the end regions 2 of the reinforcing element,adjacent to the tower shell 4, are curved, corresponding to thecurvature of the tower shell. The middle solid region of the reinforcingelement 1 is spaced from the tower shell 4 and is not connected thereto.Connection to the shell is only in the region of the trough-like ends 2of the reinforcing element. The middle region 10 of the reinforcingelement includes an upwardly open channel 18, which may havereinforcement rods therein. This channel communicates with thetrough-like ends 2 so that when reinforcing material 5, such asconcrete, is poured into the channel 18, it also fills the trough-likeends of the reinforcing element. Those trough-like ends 2 communicatewith the spaced recesses 9, and the reinforcing material extends fromthe trough-like ends into the recesses, bonding or joining thereinforcing elements to the tower shell 4. Additionally, the reinforcingmaterial 5 bonds one reinforcing element 1 to an adjacent reinforcingelement. The sealing material 16, described above in connection withFIGS. 1 and 2, prevents the leakage of reinforcing material during thisoperation. The reinforcing material 5 thus extends for the entire lengthof the reinforcing element 1 parallel to the tower shell 4.

The length of the reinforcing element 1 (as viewed in FIG. 3) is suchthat it ends about at the middle of two adjacent, spaced recesses 9.These recesses preferably are uniformly spaced around the tower shell 4.With reference to FIG. 3, the edges 14 of the trough-like end portions 2constitute projections extending toward the tower shell 4 (adjacent thecorresponding inner edge 15 of the middle solid region 10 of thereinforcing element 1). Additionally, two pairs of anchorages 19 nearthe ends of the middle region 10 are provided for anchoring thesuspension elements 7 (FIGS. 1 and 2) to the reinforcing element 1.

In summary, the preformed reinforcing element 1, after it is suspendedby the suspension elements 7 on the shell 4 and sealed with a sealingmaterial 16, is filled with reinforcing material such as concrete tofill the trough-like end portions 2, the channel 18 in the middle region10 and the recesses 9 in the tower shell 4. A closed stiffening orreinforcing ring is produced in a horizontal plane around the tower froma number of reinforcement elements, connected one to another. That ringis connected intermittently to the shell 4 of the cooling tower in thevicinity of recesses 9, spaced about the tower in the plane. Any numberof such annular stiffening rings may be so produced, as desired.

It will be apparent that the preferred embodiment described above issubject to being modified by those skilled in the art. Accordingly, theinvention should be taken to be defined by the following claims.

We claim:
 1. In a process for the production of a cooling tower formedfrom a shell of a desired form and a suitable material such asreinforced concrete, the steps comprising suspending a plurality ofplate-like reinforcing elements adjacent to a surface of said shell inat least one horizontal plane by suspension elements connected tosuspension locations on said shell above said plane, said elements in aplane substantially abutting one another, and connecting saidreinforcing elements to said shell at spaced points on said shell.
 2. Aprocess according to claim 1, in which a plurality of spaced-apartrecesses are included in at least one horizontal plane in said surfaceof said shell, and including the step of connecting together saidreinforcing elements, and in which said reinforcing elements areconnected to said shell in the region of said recesses.
 3. A processaccording to claim 2, in which, in the region where said reinforcingelements are connected together, they form an upwardly-open trough intowhich an appropriate material such as concrete is poured to connecttogether the reinforcing elements and to connect them to the shell ofthe cooling tower.
 4. A process according to claim 1, in which saidreinforcing elements are conveyed to the place of suspension on saidshell by means of a crane and are held there until installed.
 5. Aprocess according to claim 1, in which said reinforcing elements aresuspended by hand from the lowest available foothold on said shell.
 6. Aprocess according to claim 1, in which anchorages serving for thesuspension of said reinforcing elements on the shell are installed onsaid reinforcing elements.
 7. A process according to claim 1, in which asealing material is applied to the side of each reinforcing elementadjacent the cooling tower shell.